events: Update mouse-event handlers to not return EventResult.

ui/views/view.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_VIEW_H_
 #define UI_VIEWS_VIEW_H_
 
 #include <algorithm>
 #include <map>
 #include <set>
@@ skipping 634 matching lines @@
   // Widget that contains this view. Returns NULL if this view is not part of a
   // view hierarchy with a Widget.
   virtual InputMethod* GetInputMethod();
 
   // Overridden from ui::EventTarget:
   virtual bool CanAcceptEvent(const ui::Event& event) OVERRIDE;
   virtual ui::EventTarget* GetParentTarget() OVERRIDE;
 
   // Overridden from ui::EventHandler:
   virtual void OnKeyEvent(ui::KeyEvent* event) OVERRIDE;
-  virtual ui::EventResult OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
+  virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
   virtual void OnScrollEvent(ui::ScrollEvent* event) OVERRIDE;
   virtual void OnTouchEvent(ui::TouchEvent* event) OVERRIDE;
   virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
 
   // Accelerators --------------------------------------------------------------
 
   // Sets a keyboard accelerator for that view. When the user presses the
   // accelerator key combination, the AcceleratorPressed method is invoked.
   // Note that you can set multiple accelerators for a view by invoking this
   // method several times. Note also that AcceleratorPressed is invoked only
@@ skipping 826 matching lines @@
   base::win::ScopedComPtr<NativeViewAccessibilityWin>
       native_view_accessibility_win_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(View);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_VIEW_H_